Abstract: A power generating apparatus, the construction and size of which may vary from a relatively small domestic version for individual homes to a larger commercial version for power stations, comprises a device to be anchored in and driven by a substantially horizontally flowing water stream and includes a body having an endless chain horizontally mounted on sprocket wheels fixed on spaced, vertical, rotatable shafts, the chain being continuously driven by water flow driving a plurality of paddles attached thereto and arranged to be pivotable between a vertical position to be propelled downstream by water flow through a chute and a substantially horizontal position for low-drag movement upstream back to the chute inlet, track and roller support means for the paddle assemblies and a drag bar for raising and lowering the paddles from vertical to horizontal and back then to vertical position.